I have a 753. Problem started with shut down and fuel solenoid engaging randomly running battery down. Replaced ignition switch, seemed ok for a while. Problem came back replaced fuel solenoid. Seemed to fix it. Now the solenoid will not engage on its own, I can manually open and it will hold. Starts up but when I turn ignition switch off it will keep running. Disconnect battery to shut down. I have 12 volts to red wire and around 4 volts to white wire going to solenoid. If I apply 12 volts directly to white wire the solenoid functions and holds. HELP thanks in advance